PMID- 16153682
OWN - NLM
STAT- MEDLINE
DCOM- 20060623
LR  - 20240109
IS  - 0045-6535 (Print)
IS  - 0045-6535 (Linking)
VI  - 63
IP  - 2
DP  - 2006 Apr
TI  - Sequential UV-biological degradation of chlorophenols.
PG  - 277-84
AB  - The sequential UV-biological degradation of a mixture of 4-chlorophenol (CP), 
      2,4-dichlorophenol (DCP), 2,4,6-trichlorophenol (TCP), and pentachlorophenol 
      (PCP) was first tested with each pollutant supplied at an initial concentration 
      of 50 mg l(-1). Under these conditions, the chlorophenols were photodegraded in 
      the following order of removal rate: PCP>TCP>DCP>CP with only CP and DCP 
      remaining after 40 h of irradiation. The remaining CP (41 mg l(-1)) and DCP (13 
      mg l(-1)) were then completely removed by biological treatment with an activated 
      sludge mixed culture. Biodegradation did not occur in similar tests conducted 
      with a non-irradiated mixture due to the high microbial toxicity of the solution. 
      UV treatment lead to a significant reduction of the phytotoxicity to Lipedium 
      sativum but no further reduction of phytotoxicity was observed after biological 
      treatment. Evidence was found that the pollutants were partially photodegraded 
      into toxic and non-biodegradable products. When the pollutants were tested 
      individually (initial concentration of 50 mg l(-1)), PCP, TCP, DCP, 4-CP were 
      photodegraded according to first order kinetic model (r2>99) with half-lives of 
      2.2, 3.3, 5.7, and 54 h, respectively. The photoproducts were subsequently 
      biodegraded. This study illustrates the potential of UV as pre-treatment for 
      biological treatment in order to remove toxicity and enhance the biodegradability 
      of organic contaminants. However, it also shows that UV treatment must be 
      carefully optimized to avoid the formation of toxic and/or recalcitrant 
      photoproducts and results from studies conducted on single contaminants cannot be 
      extrapolated to mixtures.
FAU - Tamer, Essam
AU  - Tamer E
AD  - Department of Biotechnology, Lund University, P.O. Box 124, S-221 00 Lund, 
      Sweden.
FAU - Hamid, Zilouei
AU  - Hamid Z
FAU - Aly, Amin Magdy
AU  - Aly AM
FAU - Ossama, El Tayeb
AU  - Ossama el T
FAU - Bo, Mattiasson
AU  - Bo M
FAU - Benoit, Guieysse
AU  - Benoit G
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20050908
PL  - England
TA  - Chemosphere
JT  - Chemosphere
JID - 0320657
RN  - 0 (Chlorophenols)
RN  - 0 (Environmental Pollutants)
RN  - 0 (Sewage)
SB  - IM
MH  - Biodegradation, Environmental
MH  - Chlorophenols/*metabolism/*radiation effects
MH  - Environmental Pollutants/metabolism/radiation effects
MH  - Sewage/microbiology
MH  - *Ultraviolet Rays
MH  - Waste Management/*methods
EDAT- 2005/09/13 09:00
MHDA- 2006/06/24 09:00
CRDT- 2005/09/13 09:00
PHST- 2005/04/05 00:00 [received]
PHST- 2005/07/05 00:00 [revised]
PHST- 2005/07/10 00:00 [accepted]
PHST- 2005/09/13 09:00 [pubmed]
PHST- 2006/06/24 09:00 [medline]
PHST- 2005/09/13 09:00 [entrez]
AID - S0045-6535(05)00928-8 [pii]
AID - 10.1016/j.chemosphere.2005.07.022 [doi]
PST - ppublish
SO  - Chemosphere. 2006 Apr;63(2):277-84. doi: 10.1016/j.chemosphere.2005.07.022. Epub 
      2005 Sep 8.